WS2812 and Berry animation support for reverse-order LED strip (#24138)

Author: s-hadinger

CHANGELOG.md

@@ -5,6 +5,7 @@ All notable changes to this project will be documented in this file.
 
 ## [15.1.0.2]
 ### Added
+- WS2812 and Berry animation support for reverse-order LED strip
 
 ### Breaking Changed
 

lib/lib_basic/TasmotaLED/TASMOTALED_DOCUMENTATION.md

@@ -57,10 +57,10 @@ TasmotaLED is designed with the following principles:
                      ▼
 ┌─────────────────────────────────────────────────────────────┐
 │                   TasmotaLED Class                          │
-│  ┌──────────────┐  ┌──────────────┐  ┌──────────────┐     │
-│  │  _buf_work   │  │  _buf_show   │  │ Pixel Format │     │
-│  │  (editable)  │─▶│  (internal)  │  │  Conversion  │     │
-│  └──────────────┘  └──────────────┘  └──────────────┘     │
+│  ┌──────────────┐  ┌──────────────┐  ┌──────────────┐       │
+│  │  _buf_work   │  │  _buf_show   │  │ Pixel Format │       │
+│  │  (editable)  │─▶│  (internal)  │  │  Conversion  │       │
+│  └──────────────┘  └──────────────┘  └──────────────┘       │
 └────────────────────┬────────────────────────────────────────┘
                      │
                      ▼
@@ -116,6 +116,7 @@ TasmotaLED uses a dual-buffer system:
 │ - _type: uint16_t                                           │
 │ - _pixel_order: uint8_t                                     │
 │ - _w_before: bool                                           │
+│ - _pixel_reverse: bool                                      │
 │ - _timing: uint8_t                                          │
 │ - _started: bool                                            │
 │ - _dirty: bool                                              │
@@ -144,6 +145,7 @@ TasmotaLED uses a dual-buffer system:
 │ + GetType(): uint8_t                                        │
 │ + IsDirty(): bool                                           │
 │ + Dirty(): void                                             │
+│ + SetPixelReverse(bool): void                               │
 │ + SetRawFormat(raw): void                                   │
 └─────────────────────────────────────────────────────────────┘
                             │
@@ -171,18 +173,18 @@ TasmotaLED uses a dual-buffer system:
                             │
           ┌─────────────────┼─────────────────┐
           │                 │                 │
-┌─────────┴──────────┐ ┌────┴────────┐ ┌─────┴──────────┐
-│ TasmotaLEDPusherRMT│ │TasmotaLED   │ │ TasmotaLED     │
-│                    │ │PusherSPI    │ │PusherI2S       │
-├────────────────────┤ ├─────────────┤ ├────────────────┤
+┌─────────┴──────────┐ ┌────┴─────────┐ ┌─────┴──────────┐
+│ TasmotaLEDPusherRMT│ │TasmotaLED    │ │ TasmotaLED     │
+│                    │ │PusherSPI     │ │PusherI2S       │
+├────────────────────┤ ├──────────────┤ ├────────────────┤
 │ - _pin: int8_t     │ │- _pin: int8_t│ │(Future)        │
-│ - _channel: handle │ │- _spi_strip │ │                │
-│ - _led_encoder     │ │- _with_dma  │ │                │
-│ - _tx_config       │ │             │ │                │
-├────────────────────┤ ├─────────────┤ ├────────────────┤
+│ - _channel: handle │ │- _spi_strip  │ │                │
+│ - _led_encoder     │ │- _with_dma   │ │                │
+│ - _tx_config       │ │              │ │                │
+├────────────────────┤ ├──────────────┤ ├────────────────┤
 │ + Push(): bool     │ │+ Push(): bool│ │                │
-│ + CanShow(): bool  │ │+ CanShow()  │ │                │
-└────────────────────┘ └─────────────┘ └────────────────┘
+│ + CanShow(): bool  │ │+ CanShow()   │ │                │
+└────────────────────┘ └──────────────┘ └────────────────┘
 ```
 
 

lib/lib_basic/TasmotaLED/src/TasmotaLED.cpp

@@ -63,6 +63,7 @@ enum LoggingLevels {LOG_LEVEL_NONE, LOG_LEVEL_ERROR, LOG_LEVEL_INFO, LOG_LEVEL_D
 
 TasmotaLED::TasmotaLED(uint16_t type, uint16_t num_leds) :
   _type(type),
+  _pixel_reverse(false),
   _timing((type >> 8) & 0xFF),
   _started(false),
   _dirty(true),
@@ -175,14 +176,19 @@ void TasmotaLED::Show(void) {
     } else {
       uint8_t *buf_from = _buf_work;
       uint8_t *buf_to = _buf_show;
+      int32_t pixel_incr = _pixel_size;         // will be set to negative if reverse
+      if (_pixel_reverse) {
+        buf_from += (_pixel_count - 1) * _pixel_size;
+        pixel_incr = -pixel_incr;
+      }
       if (_pixel_size == 3) {
         // copying with swapping 512 pixels (1536 bytes) takes 124 microseconds to copy, so it's negligeable
         for (uint32_t i = 0; i < _pixel_count; i++) {
           buf_to[(*_pixel_matrix)[0]] = buf_from[0];   // R
           buf_to[(*_pixel_matrix)[1]] = buf_from[1];   // G
           buf_to[(*_pixel_matrix)[2]] = buf_from[2];   // B
           buf_to += 3;
-          buf_from += 3;
+          buf_from += pixel_incr;
         }
       } else if (_pixel_size == 4) {
         for (uint32_t i = 0; i < _pixel_count; i++) {
@@ -191,8 +197,8 @@ void TasmotaLED::Show(void) {
           buf_to[(*_pixel_matrix)[1]] = buf_from[1];   // G
           buf_to[(*_pixel_matrix)[2]] = buf_from[2];   // B
           if (!_w_before) { *buf_to++ = buf_from[3]; }
-          buf_to += 3;    // one increment already happened
-          buf_from += 4;
+          buf_to += 4;    // one increment already happened
+          buf_from += pixel_incr;
         }
       }
     }

lib/lib_basic/TasmotaLED/src/TasmotaLED.h

@@ -96,6 +96,8 @@ class TasmotaLED {
   void SetPixelSubType(uint8_t type);         // change only Pixel order and pixel size
   void _adjustSubType(void);
 
+  inline void SetPixelReverse(bool reverse) { _pixel_reverse = reverse; }
+
   bool Begin(void);
   void SetPusher(TasmotaLEDPusher *pusher);   // needs to be called before `Begin()`, sets the hardware implementation
   void Show(void);                            // pushes the pixels to the LED strip
@@ -118,6 +120,7 @@ class TasmotaLED {
   uint16_t _type;                     // the composite type
   uint8_t _pixel_order;               // permutation between RGB and position of W
   bool _w_before;                     // true if W channel comes first (4 channels only)
+  bool _pixel_reverse;                // display LED strip in reverse order
   uint8_t _timing;                    // timing code for strip, 0=WS2812, 1=SK6812...
   bool _started;                      // true if the hardware implementation is configured
   bool _dirty;                        // for NeoPixelBus compatibility, but ignored by `Push()`

tasmota/tasmota_xlgt_light/xlgt_01_ws2812_esp32.ino

@@ -636,6 +636,7 @@ bool Ws2812InitStrip(void)
     }
     uint16_t led_type = Ws2812SettingsToLedType();
     strip = new TasmotaLED(led_type, Settings->light_pixels);
+    strip->SetPixelReverse(Settings->light_pixels_reverse);
     strip->SetPusher(pusher);
     strip->Begin();
 
@@ -651,6 +652,7 @@ bool Ws2812ChangePixelCount(void)
     return true;
   }
   strip->SetPixelCount(Settings->light_pixels);
+  strip->SetPixelReverse(Settings->light_pixels_reverse);
   Ws2812Clear();
   return true;
 }
@@ -662,6 +664,7 @@ bool Ws2812ChangePixelType(bool clear)
   }
   uint16_t led_type = Ws2812SettingsToLedType();
   strip->SetPixelSubType(led_type & 0xFF);    // just submit the lower part
+  strip->SetPixelReverse(Settings->light_pixels_reverse);
   if (clear) {
     Ws2812Clear();
   } else {